I have some components which I need to use setBounds() on, hence the reason why I'm using the setLayout(null).
But some of my components are out the window(below the Y-axis). I was wondering if there is a way to add a scrollbar to navigate down the window so as to see all the remaining components. A screenshot of my window is below.
Output of my window image:
That GUI would be simple to produce using layouts. Put the component displaying the list (which looks well suited to being a JTable, given the two pieces of data per row / line) into a JScrollPane. Put the scroll pane into the CENTER of a BorderLayout. Put the red label into the PAGE_START of the border layout. Then .. oh wait, the job is done!
This is what it might look like (using a JTextArea instead of a table).
can u please post a copy of this code.
Try implementing it based on the instructions above. If there is a problem, post a minimal reproducible example of your attempt.
Since you are refering to the items in the scrolling area as components, and not as texts in a JTextArea, please have a look at the below.
import java.awt.*;
import javax.swing.*;
import java.util.Random;
public class Mainframe {
private JFrame f;
Box box;
JScrollPane scrollPane;
Random rand = new Random();
public static void main(String[] args) {
new Mainframe().go();
}
private void go() {
box = new Box(BoxLayout.Y_AXIS);
JLabel label = new JLabel("Possible Paths and Total Distances");
label.setForeground(Color.RED);
for (int i = 0; i < 200; i++) {
box.add(Box.createRigidArea(new Dimension(0, 2)));// creates space between the components
box.add(new JLabel(i + " : " + rand.nextInt(10000)));
}
scrollPane = new JScrollPane(box);
Dimension dim = new Dimension(box.getComponent(0).getPreferredSize());
scrollPane.getVerticalScrollBar().setUnitIncrement(dim.height * 2); // adjusts scrolling speed
//scrollPane.getViewport().setBackground(Color.WHITE);
f = new JFrame();
f.getContentPane().add(label, BorderLayout.NORTH);
f.getContentPane().add(scrollPane, BorderLayout.CENTER);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(640, 480);
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}
Related
edit: if you downvote this question, you may leave a comment to explain why, that will be more constructive.
I obtain this unexpected result...
... using this code:
import javax.swing.Box;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingUtilities;
public class TestAlignment extends JFrame {
// Constructor
public TestAlignment() {
super("Test Alignment");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Components to show
JLabel leftLabel = new JLabel("Left");
JButton centerButton = new JButton("Middle");
JLabel rightLabel = new JLabel("Right");
// Add all to box
Box box = Box.createVerticalBox();
box.add(leftLabel);
box.add(centerButton);
box.add(rightLabel);
box.add(Box.createHorizontalStrut(180));
// Align content in box
leftLabel.setAlignmentX(LEFT_ALIGNMENT);
centerButton.setAlignmentX(CENTER_ALIGNMENT);
rightLabel.setAlignmentX(RIGHT_ALIGNMENT);
// Add box to frame, and show frame
box.setOpaque(true);
setContentPane(box);
setVisible(true);
}
// Main
public static void main(String[] args) {
// Create frame in EDT
SwingUtilities.invokeLater(new Runnable() {
#Override public void run() { new TestAlignment(); }
});
}
}
I understand now this works as expected for JComponent.setAlignmentX(): this method tells which sides of the components must be aligned (top label leftmost side aligned with button center and bottom label rightmost side).
I would like to understand how to have each label aligned as expected intuitively (left label on the left, right label on the right), labels touching the vertical edges of the Box?
(I know how to do with putting each label in a Box embedded, and using Box.createHorizontalGlue() to force it to the left or the right side, but seems to me too much for the simple purpose of alignment. I'm looking for something more simple)
Don't think you can do this with a BoxLayout. Your example does show the intuitive code, which doesn't work as you would hope.
I would suggest you probably need to use a GridBagLayout. I think it supports the setAlignmentX(...) method the way you want to use it.
If not, then can use the Relative Layout. It is simple to use, like the BoxLayout and does support the alignment you want when you use:
setAlignment( RelativeLayout.COMPONENT );
You can use BoxLyout:
// Components to show
// Left
JLabel leftLabel = new JLabel("Left");
JPanel leftPanel = new JPanel();
leftPanel.setLayout(new BoxLayout(leftPanel, BoxLayout.X_AXIS));
leftPanel.add(leftLabel);
leftPanel.add(Box.createHorizontalGlue());
// Center
JButton centerButton = new JButton("Middle");
// Right
JLabel rightLabel = new JLabel("Right");
JPanel rightPanel = new JPanel();
rightPanel.setLayout(new BoxLayout(rightPanel, BoxLayout.X_AXIS));
rightPanel.add(Box.createHorizontalGlue());
rightPanel.add(rightLabel);
// Add all to box
Box box = Box.createVerticalBox();
box.add(leftPanel);
box.add(centerButton);
box.add(rightPanel);
box.add(Box.createHorizontalStrut(180));
// Align content in box
// leftLabel.setAlignmentX(LEFT_ALIGNMENT);
centerButton.setAlignmentX(CENTER_ALIGNMENT);
// rightLabel.setAlignmentX(RIGHT_ALIGNMENT);
I am developing a small desktop application in NetBeans. On my UI, I place a JPanel and put a single JLabel on it. The content of this JLabel is generated dynamically, so if the content is very large then it goes out of screen.So is there any way in which I can specify a fixed size for the JPanel and of course ScrollBars should appear when the text exceeds the screen size.
You will have to just pass Component reference to the JScrollPane Constructor.
It will work fine. You can definetely use JScrollPane
The following is the sudo example of the JScrollPane for JPanel from my past project. Hope it will be useful for you.
import javax.swing.*;
import java.awt.*;
public class Frame01
{
public static void main(String[] args){
SwingUtilities.invokeLater (new Runnable ()
{
public void run ()
{
JFrame frame = new JFrame("panel demo");
frame.setDefaultCloseOperation (JFrame.DISPOSE_ON_CLOSE);
JPanel panel = new JPanel();
Container c = frame.getContentPane();
panel.setSize(100,100);
panel.setLayout(new GridLayout(1000,1));
for(int i = 0; i<1000;i++)
panel.add(new JLabel("JLabel "+i));
JScrollPane jsp = new JScrollPane(panel);
c.add(jsp);
frame.setSize(100,100);
frame.setVisible(true);
}
});
}
}
Use JScrollPane to contain Your big JPanel.
so in case when the contents are very large it goes out of screen, maybe you have to look for TextComponents as JTextArea or JEditorPane, tutorial contains example including basic usage for JScrollPane
In the Navigator, click on JPanel with the right mouse button --> Enclose In --> Scroll Pane.
Done!, You have now scrolls
here's an SSCCE:
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class BoxLayoutTest extends JFrame {
public BoxLayoutTest(){
JPanel main = new JPanel();
main.setLayout(new BoxLayout(main, BoxLayout.Y_AXIS));
main.setBackground(Color.red);
this.add(main);
JPanel northPanel = new JPanel();
JPanel middle = new JPanel();
middle.setLayout(new BoxLayout(middle, BoxLayout.X_AXIS));
middle.add(new JButton("FOO"));
middle.add(Box.createHorizontalGlue());
JPanel aPanel = new JPanel();
aPanel.setBackground(Color.black);
JComboBox b = new JComboBox();
//b.setPreferredSize(new Dimension(100,16)); //uncomment this to see the layout I would like to achieve
//b.setMaximumSize(new Dimension(100,16));
//middle.add(b); //uncomment this line
middle.setBackground(Color.green);
northPanel.setBackground(Color.blue);
main.add(northPanel);
main.add(middle);
main.add(Box.createVerticalGlue());
this.setSize(800,600);
this.setResizable(true);
this.setVisible(true);
}
public static void main(String[] args) {
new BoxLayoutTest();
}
}
I'm trying to refactor some classes I wrote some time ago, when I didn't know that using setXXXSize methods on components is wrong.
Using a resizable frame ,the result I want to achieve is the following:
The northPanel should stay on top and change it's size accordingly to the frame size modifications (seems to work fine)
The green panel where I put the JButton should keep the maximum dimension of the JButton and stay just below the blue panel above (this works fine if I only put JButtons inside that panel).
The problem arise if I put a JComboBox inside the green panel (try to uncomment the line in the SSCCE). I guess JComboBox hasn't a maximum size specified, so it stretches with the frame. In the previous wrong version of my code I was using setxxxSize methods on the JComboBox to limit it's dimension(try to uncomment the line on setXXXSize methods to see it).
My question are:
Is it possible to achieve the same result using BoxLayout without invoking setXXXSize() methods?
If yes, how?
Is there any other LayoutManager that can I use to get that effect?
Please put me in the right direction
JComboBox is misbehaving (the same as JTextField) in reporting an unbounded max height: should never show more than a single line. Remedy is the same: subclass and return a reasonable height
JComboBox b = new JComboBox() {
/**
* #inherited <p>
*/
#Override
public Dimension getMaximumSize() {
Dimension max = super.getMaximumSize();
max.height = getPreferredSize().height;
return max;
}
};
just for fun, here's a snippet using MigLayout (which is my personal favorite currently :-)
// two panels as placeholders
JPanel northPanel = new JPanel();
northPanel.setBackground(Color.YELLOW);
JPanel southPanel = new JPanel();
southPanel.setBackground(Color.YELLOW);
// layout with two content columns
LC layoutContraints = new LC().wrapAfter(2)
.debug(1000);
AC columnContraints = new AC()
// first column pref, followed by greedy gap
.size("pref").gap("push")
// second
.size("pref");
// three rows, top/bottom growing, middle pref
AC rowContraints = new AC()
.grow().gap().size("pref").gap().grow();
MigLayout layout = new MigLayout(layoutContraints, columnContraints,
rowContraints);
JPanel main = new JPanel(layout);
main.setBackground(Color.WHITE);
// add top spanning columns and growing
main.add(northPanel, "spanx, grow");
main.add(new JButton("FOO"));
// well-behaved combo: max height == pref height
JComboBox combo = new JComboBox() {
#Override
public Dimension getMaximumSize() {
Dimension max = super.getMaximumSize();
max.height = getPreferredSize().height;
return max;
}
};
// set a prototype to keep it from constantly adjusting
combo.setPrototypeDisplayValue("somethingaslongasIwant");
main.add(combo);
// add top spanning columns and growing
main.add(southPanel, "spanx, grow");
I have always seen using the layout managers in the jdk are not easy. They are either too simple and inflexible or the gridbaglayout is just too much trouble. Instead I started using the jgoodies form layout and never looked back since.. Have a look at it. Its very simple and easy to use. Here's a link:
http://www.jgoodies.com/freeware/forms/
Make sure you go through the white paper.
And now, we also have google providing us a WYSISWG editor for the formlayout as a plugin for eclipse. This just makes life a lot lot easier.
http://code.google.com/javadevtools/wbpro/palettes/swing_palette.html
the problem I encountered is weird for me, because I was doing everything step by step, correctly (in my opinion) and finally when I could say I finished one part of my program it appeared to make a fun of me. The actual problem is that in GUI I created I used a JPanel, then I've put it into a JTabbedPane which I've finally put into a JFrame. Everything is fine and works apart from times when it doesn't. I know it sounds strange, but after running program once I get what I wanted (Frame with tabbed pane containing panel with some stuff in it) and then when I run it again it either show the correct thing again or just empty frame. The worst thing is that it's so random, I haven't got a clue what can be wrong, I don't even know what exactly should I google to find it out. The code is:
import java.awt.Dimension;
import java.awt.Toolkit;
import javax.swing.*;
public class GUI extends JFrame {
JFrame frame = new JFrame("WakeOnLan script generator");
JPanel panel1 = new JPanel(null);
JTextArea text; //= new JTextArea("test");
JScrollPane scroll = new JScrollPane();
JButton but = new JButton("test");
JTabbedPane tab = new JTabbedPane();
public GUI() {
Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
int w = frame.getSize().width;
int h = frame.getSize().height;
int x = (dim.width-w)/3;
int y = (dim.height-h)/4;
frame.setSize(500,500);
frame.setLocation(x,y);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.setLayout(null);
createTab1();
tab.addTab("Tab 1", panel1);
tab.setVisible(true);
tab.setBounds(0, 0, 500, 500);
frame.add(tab);
}
public void createTab1(){
text = new JTextArea("test");
text.setVisible(true);
scroll.setViewportView(text);
scroll.setBounds(10,10,465,300);
panel1.setLayout(null);
panel1.add(scroll);
panel1.setVisible(true);
panel1.setSize(500,500);
//panel.setBackground(Color.blue);
}
}
And then I just run it in the main method in other class:
public class GUIStarter {
public static void main(String[] args) {
GUI start = new GUI();
}
}
So could anyone give me an answer or just a hint?
Thank you.
You should call frame.setVisible(true) after adding all your components to your JFrame. So try moving it to the end of your constructor.
Alternatively, you can call frame.validate() after all the components have been added.
Why my JFrame 'frame' is diplaying empty window, when it should give me 3 menu buttons and my own painted JComponent below ? What am I missing here ?
import java.awt.*;
import javax.swing.*;
public class Eyes extends JFrame {
public static void main(String[] args) {
final JFrame frame = new JFrame("Eyes");
frame.setPreferredSize(new Dimension(450, 300));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel players = new JPanel(new GridLayout(1, 3));
players.add(new JButton("Eyes color"));
players.add(new JButton("Eye pupil"));
players.add(new JButton("Background color"));
JPanel eyes = new JPanel();
eyes.add(new MyComponent());
JPanel content = new JPanel();
content.setLayout(new BoxLayout(content, BoxLayout.Y_AXIS));
content.add(players);
content.add(eyes);
frame.getContentPane();
frame.pack();
frame.setVisible(true);
}
}
class MyComponent extends JComponent {
public MyComponent(){
}
#Override
public void paint(Graphics g) {
int height = 120;
int width = 120;
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
BasicStroke bs = new BasicStroke(3.0f);
g2d.setStroke(bs);
g2d.setColor(Color.yellow);
g2d.fillOval(200, 200, height, width);
g2d.setColor(Color.black);
g2d.drawOval(60, 60, height, width);
}
}
Your line:
frame.getContentPane();
doesnt do anything but access the content pane of the frame. Instead of getting the content pane, you should set your content pane, like this:
frame.setContentPane(content);
EDIT:
alternatively, as #trashgod points out, you could use the getContentPane method to access the default content pane and add your content component to that:
frame.getContentPane().add(content);
I think you are attempting to use nested JPanels. This is certainly a way to organize your components, but downside to is the fact that it gets difficult to manage in some cases. You could try this snippet of code below. In the program you will find:
1) An array of JLabel
2) An array of JTextField
3) Nested JPanels
At the end of the program I use the Container to add the final product of these object to my Graphics Window.
The most efficient way I can think of is to define these components at the top of my program so that I can reuse them later as I need to.
To achieve this you can try this snippet of code:
import javax.swing.*; //Required to use Swing Components
public class TestGUI extends JFrame
{
JLabel[] label; //Define this with an array
JTextField[] textField; //Define this with an array as well
private int nLabels; //Number of labels preferred
private int nTextFields; //Number of text fields preferred
public testGUI(int amt)
{
//Assuming that you want equal amounts of each,
//set these two variables to the "ant" input parameter
nLabels = amt;
nTextFields = amt;
//Set component attributes
label = new JLabel[2]; //Label compared text fields
textField = new JTextField[2]; //Use two of these for comparison
textField[0].setEnabled(false); //Disabled editing
//Do nothing with the second text field
JPanel labels = new JPanel(); //Place JLabels here
//Use this to align the labels vertically
labels.setLayout(new GridLayout(2, 1));
//Use this for loop to add the labels to this JPanel
for(int i = 0; i < nLabels; i++)
{
labels.add(label[i]);
//You can also define and apply additional properties
//to labels inside this loop. TIP: You can do this in
//any loop
}
JPanel txtFields = new JPanel(); //Place JTextFields here
//Use this to align the text fields vertically
txtFields.setLayout(new GridLayout(2, 1));
//Use this for loop to add the labels to this JPanel
for(int i = 0; i < nTextFields; i++)
{
textFields.add(textField[i]);
//You can also define and apply additional properties
//to text fields inside this loop. TIP: You can do
//this in any loop
}
//Now we have the two components, you asked for help with, set up
//Next, we will need another JPanel to add these to panels to.
//This JPanel will be added to the JFrame Container
//You probably know how to run this via the "main" method
JPanel window = new JPanel();
//Place the JPanel for the labels and text fields
//This requires a horizontal grid
window.setLayout(new GridLayout(1, 2));
//Add the the two JPanels: "labels" and "txtFields"
window.add(labels);
window.add(txtFields);
//Define the Container object to set up the GUI
Container container = getContentPane();
//Apply the "window" JPanel object to the container
container.add(window, BorderLayout.CENTER);
//Center this in the Graphics Window when displayed
}
//Any other methods and/or functions can be added as well
//If they are, they must placed in the constructor method above
}
This is the approach that I would use when trying to go at making and manipulating my Graphics Windows that I write. Sometimes I write applets, but only after making sure that I have everything functioning properly in a plain Graphics Window.
I hope this helps.
If you have any other questions, just let me know and I will answer the to the best of my ability, thanks.